The present invention generally relates to lighters such as pocket lighters used to light cigarettes and cigars, or utility lighters used to ignite candles, barbecue grills, fireplaces and campfires, and more particularly to such lighters which resist inadvertent operation or undesirable operation by unintended users.
Lighters used for igniting tobacco products, such as cigars, cigarettes, and pipes, have developed over a number of years. Typically, these lighters use either a rotary friction element or a piezoelectric element to generate a spark near a nozzle which emits fuel from a fuel container. Piezoelectric mechanisms have gained universal acceptance because they are simple to use. U.S. Pat. No. 5,262,697 (xe2x80x9cthe ""697 patentxe2x80x9d) to Meury discloses one such piezoelectric mechanism, the disclosure in the ""697 patent is incorporated by reference herein in its entirety.
Lighters have also evolved from small cigarette or pocket lighters to several forms of extended or utility lighters. These utility lighters are more useful for general purposes, such as lighting candles, barbecue grills, fireplaces and campfires. Earlier attempts at such designs relied simply on extended actuating handles to house a typical pocket lighter at the end. U.S. Pat. Nos. 4,259,059 and 4,462,791 contain examples of this concept.
Many pocket and utility lighters have had some mechanism for resisting undesired operation of the lighter by young children. Often, these mechanisms are on/off switches which may shut off the fuel source or may prevent movement of an actuator, such as a push-button, on the lighter. On/off switches which a user positively moves between xe2x80x9conxe2x80x9d and xe2x80x9coffxe2x80x9d positions can be problematic. For example, an adult user may forget to move the switch back to the xe2x80x9coffxe2x80x9d position after use and thereby render the feature ineffective.
Other pocket and utility lighters include a spring-biased blocking latch which arrests or prevents movement of the actuator or push-button. U.S. Pat. No. 5,697,775 to Saito and U.S. Pat. No. 5,145,358 to Shike, et al., disclose examples of such lighters.
There remains a need for lighters which resist inadvertent operation or undesirable operation by unintended users, but which provide each intended user with a consumer-friendly method of operating the lighters so that the lighters appeal to a variety of intended users.
The present invention relates to a lighter, such as a pocket lighter or a utility lighter. The lighter includes a housing having a supply of fuel, an actuating member movably associated with the housing to selectively ignite the fuel, and a latch moveable between a first latch position and a second latch position to vary the amount of force required to move the actuating member to ignite the fuel. When a user attempts to move the latch before moving the actuating member, a first latch force is required to move the latch from the first latch position to the second latch position. When a user moves the actuating member a predetermined distance before moving the latch, a second latch force is required to move the latch from the first latch position to the second latch position. The second latch force is different than the first latch force.
When the latch is positioned in the first latch position (e.g., the xe2x80x9chigh-force modexe2x80x9d), the user applies a first actuating force to the actuating member to ignite the fuel, and when the latch is positioned in the second latch position (e.g., the xe2x80x9clow-force modexe2x80x9d), the user applies a second actuating force to the actuating member to ignite the fuel. The first actuating force is different than the second actuating force. Preferably, the first actuating force is greater than the second actuating force.
According to one embodiment, the second latch force may be greater than the first latch force. Alternatively, when a user moves the actuating member a predetermined distance before attempting to move the latch, the latch may be substantially prevented from movement from the first latch position to the second latch position.
The lighter may include a first engagement surface associated with the latch, and a second engagement surface associated with the actuating member, and upon movement of the actuating member a predetermined distance before movement of the latch, the first engagement surface may engage the second engagement surface. Furthermore, upon movement of the latch before movement of the actuating member, the first engagement surface may be substantially disengaged from the second engagement surface. The lighter may further include a plunger member associated with the latch, and the first engagement surface may be formed on the plunger member. The actuating member may be a trigger, and the second engagement surface may be formed on the trigger.
The first engagement surface may be inclined or angled, and the second engagement surface may also be inclined or angled, for example to match the first engagement surface. Alternatively, the first and second engagement surfaces may be overlapping horizontal surfaces that abut one another upon movement of the actuating member before movement of the latch, however, one of ordinary skill in the art will recognize that any number of configurations of the first and second engagement surfaces are possible and contemplated by the present invention.